How will I know if I have ketones?

Ketones are very easy to test for. When your body is high in ketones, it tries to get rid of them very quickly. It does this by pushing them out in your urine. Testing your urine for ketones will give you a clear indication of how high your blood ketones are.

What does having ketones mean?

You develop ketones if you are not having enough insulin. Your insulin needs will change in certain situations. When you are sick or injured, your body becomes resistant to the action of insulin (your insulin can’t work properly) and your body’s need for energy increases. This is because your body needs extra energy to fight infection or heal from an injury. So to put it simply, having ketones means your body needs more insulin.

When should I test for ketones?

You should test for ketones either when your blood glucose is more than 17mmol/L OR if your blood glucose is climbing and you feel unwell, OR if you are injured and your ketone levels are increasing.

How do I test for ketones?

That depends on what sort of ketone testing strips you have. At the moment ketone testing that you do at home is always done on your urine.

At what level of ketones in my urine should I be concerned?

A trace to a small amount of ketones in your urine is usually okay. However, if you are showing small amounts of ketones and you are unwell you should keep a careful eye on whether they are increasing or coming down. Get help if they continue to increase.

If you are showing a moderate or large amount of ketones in your urine you need to act quickly to bring them down. You should ALWAYS contact your doctor or diabetes nurse educator if you have a moderate or large amount of ketones in your urine. If you can’t get immediate advice, you should go to the nearest hospital. If your ketones are high and you are feeling unwell this trip to the hospital should be in an ambulance.

Other things you can do for yourself if your ketones are raised, but not too high, are:

  • Drink water. If your ketone levels are small or moderate AND you are feeling unwell, you need to start drinking large amounts (2-3 litres) of water daily
  • Take more insulin. You should also take more short-acting insulin. If you have not been taught how to do this (and what dosages to take), you must get help and guidance on this from your diabetes team. Don’t take extra insulin unless you know how to dose for sickness
  • Test your blood and your urine. You should also test both your blood glucose and urine ketone levels every 1 – 2 hours until the ketones are cleared and your blood glucose levels are coming down


You should get help if:

  • Your urine ketone levels are high
  • Your urine ketone levels are not coming down once you have started treating yourself for ketones
  • You are feeling very unwell (drowsy, rapid breathing, pain in your abdomen or nausea and vomiting)
  • You are unable to look after yourself
  • You don’t know how much extra insulin to take
  • You are unable to drink fluids
  • You have a temperature or an obvious sickness that is not improving



Key points

  • Home urine ketone testing lets people with Type 1 diabetes know if they are in danger of going into diabetic ketoacidosis (DKA) (High Blood Glucose).

  • Home urine glucose testing is now only recommended for those people who can’t test their own blood glucose levels. It is a very inaccurate way of testing.


Testing for ketones in your urine is an essential and very useful tool when you have Type 1 diabetes. It can save you a trip to hospital. It can also save your life. Having high levels of ketones in your body is a life threatening condition. Having ketone testing sticks and knowing how to use them enables you to pick up when your ketone levels are increasing. Once you know this is happening then you are able to manage it. See our high blood glucose Type 1 section for more on ketones and management.


What ketone sticks should I use?

For most purposes, the individually foil wrapped ketone sticks that you can buy from many chemists are the best. Because they are foil wrapped they are less likely to go off. Also it is easy to carry two or three strips in your blood glucose meter case. This way if you are out you will have them with you if you need them.


Remember to also carry the colour guide chart with them so if you do need to test you are able to read the result! Remember to also check the expiry date on your sticks every now and again. This avoids having expired sticks at the time you most need to know what your ketone levels are.


When should I test for ketones?

You should test for ketones in your urine when:

  • Your blood glucose is going up (at any level) and you are feeling unwell
  • Your blood glucose is greater than 17mmol/L and it is not coming down (even if you feel well)
  • You are unable to test your blood glucose but you feel unwell
  • You develop abdominal pain and/or nausea and vomiting